Definition
A busway, sometimes called busduct, is a prefabricated modular power-distribution system in which solid copper or aluminum conductors (busbars) are enclosed in a grounded metal housing. Instead of pulling individual cables in conduit to every rack, a facility runs a busway overhead and taps power off it at intervals. It is governed in North America by UL 857 and has become a standard for high-density mining and data-center power.
Plug-in and tap-off architecture
The defining feature is the ability to draw power along the run. Plug-in busway provides tap-off windows at fixed intervals where a plug-in unit (often feeding a power whip and then a rack PDU) clips on. Open-channel or 'track' busway goes further, offering a continuous slot so tap-off devices can be added, moved, or repositioned anywhere along the length, in many designs without de-energising the system.
Why mining and data halls prefer it
Compared with conduit-and-cable, busway is faster to install, more compact, and far more scalable: new circuits can be added by clipping on a tap unit rather than pulling new wire back to a panel. In a mining facility where machine count and layout change frequently, that repositionability cuts both cost and downtime. The enclosed busbars also handle very high currents in a small cross-section, which suits the dense, high-amperage loads of an ASIC hall.
Trade-offs
Busway carries a higher up-front material cost than cable and requires careful planning of the run and rating. For long, fixed, low-change installations, conventional cabling can still be cheaper.
For the flexible drop that connects a busway tap to a rack see the power whip, and for the connectors at the rack PDU see the IEC 60320 C19 / C20 connector.
In Simple Terms
A busway, sometimes called busduct, is a prefabricated modular power-distribution system in which solid copper or aluminum conductors (busbars) are enclosed in a grounded metal…